The display has gone blank. Is my ZEN Thermostat still working?

The ZEN Thermostat displays turns off when you're not interacting with it. ZEN does this because we believe connected home devices should blend into the background of your home when you don’t need them. This approach also helps the ZEN maintain a long battery life.

Even when the display is off, ZEN keeps controlling your heating and cooling, and you have full control via your home-automation system as well.